What happened to the Universe soon after its creation and how it evolved afterwards, are among the most exciting questions the mankind could now explore. Understanding the so-called "dark ages" and the problem of dark matter and dark energy are among the most outstanding unknowns in modern cosmology today. During the dark ages, the first generation of galaxies were formed and today, we can indeed search and study them. At the other hand, dark matter and dark energy govern the evolution of our Universe and control its destiny. In my talk, I present the latest results from Hubble Space Telescope observations regarding search for the first generation of galaxies and what we know today, regarding the nature of dark matter and dark energy.